Se Bin, Gi Chan, and Sang Mi are the students in the 'Troubled Teens' group whose 'disturbing behaviour' contribute to dropping their high school's national rank. The principal decides to hire ex-dropout Hwang Gi Poong as the music class teacher and counsellor to these misfits in hopes that someone with a similar background could ease them up a bit. In order to boost the kid's self-respect, Gi Poong decides to enter them
